An RFID tag having an IC chip for storing information and an antenna used for transmitting/receiving the information is known as a tag for RFID. The IC chip of the RFID tag is activated in response to a radio wave received from a reader/writer for reading/writing the information, to transmit the information stored in the IC chip in the form of a radio wave. This RFID tag is attached to, for example, an object, for the purpose of managing the object.
When the RFID tag is attached to a surface of a metallic object, electromotive force that is induced in the antenna is lowered by the radio wave transmitted from the reader/writer. As a result, the IC chip cannot be activated.
As such an RFID tag that can be attached to a surface of a metallic object, there is an RFID tag having an IC chip and antenna stored in a container (e.g., TFU-TM28×B, a tag for a small metal, manufactured by Fujitsu Frontech Limited).
There is also an RFID label that has a tubular RFID holder with a rectangular cross section, which holds an IC chip and antenna, and an attached part bonded to an object (see Patent Document 1, for example). The RFID holder of the RFID label according to Patent Document 1 can protrude in a direction away from the object. Therefore, the IC chip and the antenna can have a sufficient distance with the metallic object. The RFID label according to Patent Document 1, therefore, can be attached to a surface of the metallic object.
Patent Document 1: Japanese Patent Application Publication No. 2007-172369
For example, steel mills and other factories often use RFID tags, for the purpose of managing plate-like objects such as metal plates. Normally, the plate-like objects are disposed by stacking a plurality of flat plate surfaces thereof one on top of the other. In order to manage the plurality of the stacked plate-like objects, the RFID tags are preferably attached to side surface of the objects perpendicular to the flat plate surfaces instead of being attached to the flat plate surfaces.
Therefore, when the areas or widths of the surfaces of the objects to which the tags are attached (referred to as “attached surfaces of the objects,” hereinafter) are too small, the areas or widths of attached surfaces of the RFID tags need to be reduced in accordance with the areas or widths of the attachment surfaces of the objects to which the tags are attached. This might make the RFID tags fall off the objects easily.
However, in the abovementioned RFID tag using a container, one flat surface of the container is configured as an attachment surface by being applied with, for example, an adhesive.
Furthermore, the RFID holder of the RFID label according to Patent Document 1 is in a cylindrical shape. For this reason, the bottom of the RFID holder cannot be configured as an attachment surface. This RFID label therefore provides poor attachment stability.
It is, therefore, difficult to stably attach the conventional RFID tags to the side surfaces of plate-like objects.